Automatic coffee maker



Feb. 4, 1936. 5 mm 2,029,596

AUTOMATIC COFFEE MAKER Filed Dec. 19, 1932 2 Sheets-Sheet l 1765- 1936- J. E. SMITH AUTOMATIC COFFEE MAKER 2 Sheets-sheaf 2 Filed Dec. 19, 1952 v Z WWW I I z z 7 fl /o 5. Z u u/o H w a 2 ..I 5 .I II I i w A 1 CURRENT SUPPLY 55 CURRENT IIIIIIIII I I I I I I Patented Feb. 4, 1936 AUTOMATIC COFFEE MAKER John E. Smith, Belleville, IIL, assignor to Knapp- Monarch Company, Belleville, 111., a corporation of Missouri Application December 19, 1932, Serial No. 647,842

2 Claims.

An object of my present invention is to provide a device for making coffee by the drip process, the device being in the form of an electric appliance and being comparatively simple and inexpensive to manufacture.

A further object'is to provide a coiiee maker comprising a liquid coffee receptacle having a coiiee cup depending therein for containing ground or granulated coffee with a water receptacle above the coiiee cup adapted to contain and heat water prior to introduction of the water into the coffee cup through the contents of which the water drips to produce the liquid coffee.

A further object is to provide valve means to prevent premature admission or" the water to the coiiee cup before the water has been heated to the necessary degree to properly make the codes by the drip process.

Still a further object is to provide a valve plug for normally closing the valve which can be in the form of a stem secured to the lid of the water receptacle and disengageable from the valve seat when the lid is removed, or can be in the form of a combination armature and valve plug which can be opened by a solenoid or the like.

Still a. further object is to provide thermostatic means for controlling the supply of electric current to the heating element for the water in the water receptacle.

Still another object is to provide a solenoid for opening the valve connected with the thermostat so as to be automatically controlled thereby, the thermostat being responsive to the temperature of the water being heated in the water receptacle.

Further objects are to provide novel means for securing the heating element and other parts of the construction together and for supporting the thermostat.

With these and other objects in view my invention consists in the construction, arrangement and combination of the various parts of my device, whereby the objects contemplated are attained, as hereinafter more fully set forth, pointed out in my claims, and illustrated in the accompanying drawings, in which:

Figure 1 is a perspective view of a coffee maker embodying my invention.

Figure 2 is a vertical sectional view of the same on the line 2-2 of Figure 1.

Figure 3 is a sectional view on the line 3-3 of Figure 2 showing the parts on an enlarged scale.

Figure 4 is a sectional view on the line 4 -4 of Figure 3 showing a bottom plan view of parts of the device.

Figure 5 is a side elevation showing the lid on the water receptacle in Figure 2 mounted on the liquid cofiee receptacle.

Figure 6 is a diagrammatic view of the wiring for the preceding figures.

Figure 7 is a sectional view similar to Figure 3 5 showing a modified construction.

Figure 8 is a sectional view on the line 8-8 of Figure 7; and

Figure 9 is an electrical diagrammatic view of the form of invention shown in Figures '1 and 3. 10

On the accompanying drawings, I have used the reference numeral iii to indicate a liquid coffee receptacle. It has a spout l2 and a handle it for convenience in pouring and handling the receptacle ill.

Depending within and removable from the liquid coffee receptacle ill, is 'a. coiiee cup iii. It has a bottom it provided with a, great number of small perforations. Frictionally mounted in the cofiee cup it is a spreader plate It is also perforated but the perforations are larger and there are not so many of them. The spreader plate 20 has a depression 22 at its center.

Frictionally received in the spreader plate 28 (which is of cup-1ike formation as clearly shown 25 in Figure 2) is a housing 24. A water receptacle 28 extends into the housing 2% and is secured thereto as will now be described.

A valve seat element 28 is associated with the bottom of the water receptacle 26 (see Figure 3). 30 It is secured in position by being screwed into a sleeve member 39. The sleeve member is threaded to receive a nut 32. The nut holds the housing 24 in assembled relation to the water receptacle 26.

Against the bottom of the water receptacle 26 I provide a. heating element 34 in the form of a coil of resistance wire imbedded in argillous material. A heating element casing 36 is provided for the heating element S l. Y

The casing 36 is retained in position against the bottom of the receptacle 26 by a spacer 38 which is interposed between the casing and the housing 24. It is perforated for the sleeve 30 to extend through.

On the sleeve 30 I provide a stationary spring 40 having a contact 42 and a thermostatic bar #4 having a contact 46. These are mounted on an insulating sleeve 48 and between insulating washers 50, all of which are retained in assembled po- 50 sition on the sleeve 30 by a nut 52.

As shown in Figure 6, one end of the heating element 34 is connected with the spring 40 and the other end is connected with a contact prong 54. A second contact prong 56 is connected with the thermostatic bar 44, thus placing the thermostat in series with the heating element 345. The prongs 5d and 56 are adapted to coact with the socket member of an appliance cord in the ordinary manner.

A valve plug 58 is provided for the valve seat 28. The plug is on the lower end of a stem 80 which is connected with a cover 62. The cover 62 is adapted to fit either the receptacle 26 or the receptacle Hi. When in position on the receptacle 28, it is slightly spaced from the upper edge thereof, as shown in Figure 2, so that the plug 58 is held by the weight of the cover against the valve seat 28.

In the modified construction of Figures 7, 8 and 9, the heating element 36, prongs 56 and 56 and spring and thermostat 4D and M are used, but a solenoid E l is connected in the circuit for automatically disengaging a valve plug 5811 from a valve seat element 28a. As shown in Figure 7, the assembly of the housing 2% relative to the receptacle 26 is slightly different. A sleeve 30a is welded or otherwise secured to the bottom of the receptacle 26 and the valve seat member 28av takes the place of the nut 32 in Figure 3. The solenoid 6d surrounds the sleeve 36a. A valve stem 60a in Figure 7 is of magnetic material such as iron, so that it forms an armature to be attracted by the solenoid coil M when it is energized for thus lifting the valve plug 58 from its seat.

The thermostat 6 3 is mounted differently than in Figure 3. It is carried by an insulating block 66 which in turn is supported by a casing 68. The spring 60 is secured to the block 66.by a screw l0. The contact 62 is screw-threaded through the spring Q0 and thereby adjustable relative thereto. A spring '12 serves the purpose of retaining the contact 412 in adjusted position.

The heating element 36 is imbedded in a casing 35a and the casing is mounted inside the receptacle 26. Ends 36b are provided which extend through the bottom of the receptacle 28 and have terminals 340.

In the operation of the coffee maker shown in Figures 1 to 6 inclusive, the unit consisting of the receptacle 26, cover 62, housing 24 and spreader plate 20 are removed from the receptacle l0 whereupon the desired quantity of granulated coffee may be placed in the coffee cup I6. The removed unit may then be replaced and the cover 62 removed. The proper quantity of water may then be poured into the receptacle 26 whereupon the cover 62 should be immediately replaced to prevent more than a few drops of water from flowing past the valve seat 28. The prongs 54 and 56 are then connected with a source of current supply whereupon the heating element 34 will be energized for heating the water in the receptacle 26.

The heat of the water will be transmitted through the bottom of the receptacle 28, the sleeve 30 and the heating element casing 36 to the space in the housing 26 surrounding the thermostatic bar 46.

At a predetermined temperature of the water, the bar will have warped sufiiciently to separate the contacts 62 and 46, thus preventing the water from becoming hotter than a predetermined temperature.

After the thermostat has operated, the cover 62 may be lifted for raising the valve plug 56 from the valve seat 28 and an extension 59 may then be adjusted to the dotted line position oi Figure 3 to retain the valve in open position. The heated water will flow into the depression 22 of the spreader plate 20 and be spread too by the plate to drip evenly over the coffee in the cup it. It will slowly flow through the cofiee and drip from the perforations in the bottom it. At the time the cover 52 is lifted, the source of current should be disconnected because there is no need of further heat if the cofiee is consumed within a reasonable period of time. 1

After the drip process has been completed, the cofiee l6 and all parts thereof may be removed from the receptacle It and the lid 62 placed thereon, as shown in Figure 5, so that the receptacle ltl can be used as a pouring pot for the liquid cofiee.

In the operation of the form of invention shown in Figures 7, 8 and 9, the" coflee and water are placed in the cup l5 and the receptacle 28 respectively and the heating element lid is energized. When the temperature of the water causes the thermostat it to operate, the solenoid 5 3 will be thrown into the circuit for automatically opening the valve 58a.

The valve will remain open until the operator disconnects the electric circuit which of course should not be done until after all the water has flowed through the valve. The slight amount of current flowing through the heating element 36 while the solenoid 643 is energized serves to main tain the water in the receptacle 26 at the temperature to which it was heated while it is flowing through the valve seat 28a.

Some changes may be made in the construction and arrangement of the parts of my device without departing from the real spirit and pur= pose of my invention, and it is my intention to cover by my claims, any modified forms of structure or use of mechanical equivalents, which may be reasonably included within their scope.

I claim as my invention:

1. In an automatic cofiee maker, a liquid cofiee receptacle, a perforated coffee cup thereabove for holding granulated cofiee, a water receptacle above said coffee cup, a passageway for providing communication between said water receptacle and said coffee cup, a normally closed valve in said passageway, electro-responsive means for opening said valve when said means is energized, an electric heater element for said water receptacle, current supply terminals, and a temperature responsive switch responsive to the temperature of the water in said water receptacle rising to a predetermined degree, whereupon. said switch completes the circuit from said terminals through said electro-responsive means whereby to fully open said valve and retain it fully opened upon such predetermined degree of temperature being reached, said heating element and temperature responsive switch being connected in series between said terminals and said electro-responsive means being connected in shunt with said switch whereby upon opening of said switch due to said pletes the circuit to said electro-responsive means whereby to discharge said heated water to said ooflee cup upon such predetermined degree oi temperature being reached, said heating element and temperature responsive switch being connected in shunt with said electro-responslve means whereby upon opening or said switch due to said temperature rise, said heating element and said electro-responsive means are connected in series.

JOHN E. SMITH. 

